Somatic growth in infant heart transplant recipients

Abstract

Infant heart transplantation is now entering its second decade of clinical experience. To understand better issues relating to somatic growth, this retrospective study will describe growth patterns in a group of infant heart transplant recipients. Early growth: growth velocity from birth to transplantation in 77 infants transplanted before 6 months of age was compared with growth velocity from transplant to 3 months. Growth from 3 to 6 months and from 6 to 12 months after transplantation is described. Growth velocities (mean +/- SD) for weight (g/d) and length (cm/yr) for these 4 time periods respectively were: 7+/-14 and 27+/-22, 32+/-9 and 35+/-14, 17+/-7 and 24+/-10, 12+/-6 and 17+/-8. Growth velocities for both weight (p<0.01) and length (p = 0.04) were significantly improved in the first 3 months after transplantation. Late growth: Growth beyond 5 yr post-transplantation was described in a group of 51 infants transplanted in the first year of life and who survived at least 5 yr (median 6.8 yr, range 5.0 to 10.9). Most recent growth parameters (z-score; mean +/- SD) were: weight -0.55+/-1.2, height -0.48+/-0.97 and weight for height -0.16+/-0.96. Factors (with significant p-values) evaluated for their possible influence on late height (<5th percentile vs. > or =5th percentile) were: age at transplant, hospital days from transplant to discharge, hospital days 1st year after transplantation (p = 0.019), hospital days after 1st year, rejection episodes 1st year, rejection episodes 1-5 yr (p = 0.02) mid-parental height (p = 0.008) and isotopic glomerular filtration rate (p = 0.055).

Conclusion: Growth while awaiting infant heart transplantation is poor, but adequate catch-up growth does occur. Beyond 5 yr most (88%) infant heart transplant recipients have weight and height in the normal range. Early illness, late rejection and genetic growth potential may play the largest role in later height attainment.